miércoles, 10 de junio de 2009

Lo prometido es deuda!!!



Hi everybody!!! How is it going?
As I promised few days ago, I already uploaded the files containing the information about the design projects as well as a form you should fill up with the information about your team... Check out the "Download Page"...
I promised an exercise too so there you go...
Take care...
Alfredo Alvarez!

EJERCICIO

Se desea diseñar un compresor centrífugo de una etapa, procurando una entrada del fluido sin prerrotación a través de un área de 25cm2. Para asegurar un diseño sub-sónico Umax=280m/s. El motor de accionamiento gira a 3000rpm. d2/d1=2,1. Si Beta2=50° y Vr1=200m/s, y ; defina:
a) Ángulo Beta 1
b) El trabajo específico requerido
c) El Caudal de Operación Óptimo
d) La Potencia del motor
e) El grado de reacción

6 comentarios:

eduar gutierrez dijo...

hola esta buena esta pajina explican el funcionamiento de un impulsor en una bomba

http://www.youtube.com/watch?v=XkYW6725kAc

eduar gutierrez dijo...

aliniacion de un sello mecanico de una bomba
http://www.youtube.com/watch?v=nNH4xgR2Iaw&feature=related

Anónimo dijo...

Hi everyone, here are some of topics about Turbo-Machines:

CAVITATION

Cavitation occurs when pressure in the suction line falls below vapor pressure, vapor is formed and moves along with the stream. These vapor bubbles or cavities collapse when they reach regions of higher pressure on their way through the pump. The most obvious effects of cavitation are noise and vibration.


PREVENTING CAVITATION

Cavitation is prevented by preventing vapor formation within a pump

TEST TO CONFIRM HIGH VELOCITY CAVITATION

Close pump discharge control valve to reduce flow .If pump noise significantly reduces and conditions become stable, cause is confirmed

Anónimo dijo...

A pump is defined as a device that moves a liquid by increasing the energy level of the liquid. The pumps are divided into two distinct groups. One group pumps the liquid by means of positive displacement - the other group pumps the liquid by means of dynamic action.

Positive displacement
Increase pressure by operating on a fixed volume in a confined space

Types

Screw, gear, reciprocating

Characteristics

• Constant volume
• Variable differential head
• Relatively insensitive to liquid properties
• Relatively insensitive to system changes
• Not self-limiting

Dynamic
Increases pressure by using rotary blades to increase fluid velocity

Types


Centrifugal axial

Characteristics

• Variable volume
• Constant differential head
• Sensitive to liquid properties
• Sensitive to system changes
• Self-limiting

Anónimo dijo...

CENTRIFUGAL PUMP APPLICATIONS

• The following is not meant to be a complete list of centrifugal pump applications, but an illustration the versatility of this type of pump.

Water Supply

 Low-lift pumps
 sampling pumps
 wash water pumps
 High-service pumps
 Booster pumps

Ground Water Wells

 vertical turbine line-shaft pump
 submergible pump

Sewage Treatment

 raw sewage pump
 settled sewage pump
 service water pump
 dilute sludge and scum pump

Drainage and Irrigation

 deep well turbine pump
 submergible turbine pump
 propeller pumps
 volute pumps

Fire Pumps

 vertical turbine pump
 horizontal volute pump

Steam Power Plants

 condensate pumps
 heater drain pumps
 condenser circulating pumps
 boiler circulating pumps
 ash-handling pumps

Petroleum

 crude distillation pumps
 vacuum tower separation pumps
 catalytic conversion pumps
 alkylation pumps
 hydro cracking pumps
 coking pumps
 pipeline pumps

Pulp and Paper Mills

 heavy-black-liquid pumps
 digester-circulating pumps
 low- and intermediate-concentration stock pumps

Mining

 All applications for open pit and deep mines including control of seepage, rainwater, and service water.

Food and Beverage

 Used throughout the industry except when metering is required or when high viscosities such as dough or cottage cheese must be handled.

Refrigeration, Heating, and Air Conditioning

 cooler tower water circulating pumps
 hot water circulating pumps
 brine circulation pumps
 refrigerant circulation pumps

Anónimo dijo...

Hey what's going on?,The following topics are about basic information the meaning of some equations for pumps design.

NET POSITIVE SUCTION HEAD AVAILABLE (NPSHA)
• Available NPSH is a characteristic of the pumping system. It is defined as the energy that is in a liquid at the suction connection of the pump.

NET POSITIVE SUCTION HEAD REQUIRED (NPSHR)
• Required NPSH is the energy needed to fill a pump on the suction side and overcome the frictional and flow losses from the suction connection to that point in the pump at which more energy is added. Required NPSH varies with pump design, pump size, and operating conditions and is supplied by the pump manufacturer.

BERNOULLI’S THEOREM
• Energy cannot be created or destroyed. The sum of three types of energy (heads) at any point in a system is the same in any other point in the system assuming no frictional losses or the performance of extra work.

BRAKE HORSEPOWER
• Brake horsepower is the total power required by the pump to do a specified amount of work.


VISCOSITY

• Viscosity is the internal friction of the liquid or that property that resists any force tending to produce flow. Absolute (or dynamic) viscosity is usually expressed in centipoise.

• Kinematic viscosity is the ratio of absolute viscosity to density and is expressed in centistokes (SSU). with temperature change, decreasing as the temperature is
increased.

• Many liquids such as water and mineral oil are considered Newtonian and do not change in viscosity with a change in rate of shear or agitation. Liquids such as grease, syrups, glues, and varnishes are called Thixotropic. These show a marked reduction in viscosity as the rate of shear is increased. Other liquids such as clay slurries, some starches and paints, and milk chocolate with filler are referred to as
Dilatant. They show an increase in viscosity as the rate of shear is increased.

• Viscosity is measured by viscometers such as Saybolt (U.S.), Bedwood (U.K.), and Engler (Germany).